Zimmerman had to use deadly force because Martin was using deadly force.

Martin was using deadly force because Zimmerman was the aggressor and was armed with a deadly weapon.

Zimmerman lived and so he got to tell the story if how even though he tracked his victim like a hunter, the real victim was him because Martin apparently went home, calmed down, had a sandwich, tool a bubble bath and then all of a sudden out if nowhere decided to go murder Zimmerman, using only his bare hands and no sort of weapon or anything that might be useful to murder someone with. Right.

The argument Martin would make had he beaten Zimmerman to death was that Zimmerman was armed and deadly and had followed him with a gun, essentially hunting him, and he had to use deadly force to try to disable this crazed stalker with a gun.

The bottom line is one guy went hunting another, cornered him, raised the stakes to life or death by showing his weapon, got the expected reaction from his victim, then used that to justify deadly force. It's a brilliant hack. Congrats to him.

Add to it an unverifiable story about the victim making it home and coming back out, and it's the perfect crime.

It could have worked in Portland too, but there were too many video cameras running. And racism wasn't on the side of the attacker in the Portland case.